Skincare 101

All the sunscreen basics you need to know before summer kicks off

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quick advice

When applying sunscreen for the pool or beach, picture a hotel shampoo amenity bottle – it’s usually 1.5 ounces. That's how much you need.

Why sunscreen daily?Oh, so many reasons. But we’ll start with the fact that 90% of visible signs of aging are caused by the sun. And unless you’re living in a cave, you are exposed to the sun daily (including UVA rays you might not notice) and your body counts sun exposure cumulatively. We may get wiser over the years, but we also collect more sun-time. And the damage shows up many, many years later.

Chemical SunscreenContaining ingredients like avobenzone, homosalate, octinoxate and others, chemical sunscreens absorb the sun’s rays, transform them into heat, which is then released from your skin. ‘Chemical’ sounds like a bad word, but it’s not here – it just describes how it functions. Chemical sunscreens take about 20 minutes to activate after application, so lotion up before heading out.

Physical SunscreenPhysical sunscreens are ones with zinc oxide or titanium dioxide and work like a mirror, deflecting the sun’s rays from your skin. They can be less likely to clog pores, cause less allergy issues, and are ideal for everyday use, especially on your face. And they’ve come a long way from the white-nose days, so don’t worry about that. Protection is instant once applied.

UVA vs. UVB RaysThe A and B letters are scientific, but all you have to remember is A for Aging and B for Burning. UVB rays cause familiar results – sunburns. UVA rays do quieter damage, causing wrinkles, skin cancer, and visible signs of aging. UVA rays come through clouds and windows, which is why we preach daily sunscreen.

Broad SpectrumSunscreen labeled ‘Broad Spectrum’ protects against both UVA and UVB rays. If it’s not labeled as such, chances are it’s only covering UVB rays (think: your less expensive body sunscreens you’ll find at the drug store). You’re best off with Broad Spectrum to make sure you’re covered, especially when it comes to your face.

The SPF NumbersSun Protection Factor (SPF) is a standard laboratory measurement of a sunscreen’s ability to prevent UVB damage to our skin. (Important distinction, it doesn’t measure the impact of those aging UVA rays.) If it normally takes you ten minutes to burn, generously-applied SPF 30 would keep you from burning for 300 minutes, or about five hours. (Usual Time To Burn x SPF = Protection Time). Our take? Math is not fun at the beach, so do yourself a favor and just re-apply often and liberally.

How much sunscreen?Conventional wisdom says a ‘shot glass’ worth over your entire body, but we’d rather not reminisce over shot glass days. Picture a hotel shampoo amenity bottle – it’s usually 1.5 ounces. It’s all of that, in one go. Now you can picture why most people apply about half as much as they should (!). Apply more frequently if you’re sweating or jumping in the water.

Over or under makeup?We’re fans of straight up sunscreen over powered foundations with SPF to ensure coverage. (Or both if you’re doing foundation). SPF with moisturizer can go under makeup. We love the Prevention+ from Image and the City Sunscreen Serum from Supergoop! Supergoop! also has a Defense Refresh Setting Mist for a matte finish post-makeup look with SPF 50 protection.

When was this stuff invented?Need a fact for your summer barbecue? The first major commercial sunscreen was sold in 1936, by the founder of L’Oreal. Ten years later, it improved dramatically for soldiers in World War II. “SPF” as a standard was adopted in 1974. And before all that, ancient cultures used olive oil, rice extract, zinc oxide, and other compounds for thousands of years.